1. Field of the Invention
The present invention relates to a recording tape cartridge which accommodates, within a case, a single reel on which is wound a recording tape, such as a magnetic tape or the like, which is used mainly as a recording/playback medium for computers or the like.
2. Description of the Related Art
There have conventionally been known recording tape cartridges in which a recording tape, such as a magnetic tape or the like which is used as a data recording/playback medium for computers or the like, is wound on a single reel, and the reel is accommodated within a case. Such a recording tape cartridge has a substantially rectangular box-shaped case. As shown in FIGS. 16A and 16B for example, a case 102 of a recording tape cartridge 100 is structured by an upper case 104 and a lower case 106, each of which is substantially shaped as a tray, being joined together in a state in which peripheral walls 104A, 106A thereof abut one another. A single reel 108, on which a recording tape T is wound, is rotatably accommodated within the case 102.
A leader member 110, such as a leader tape or the like, is fixed to an end portion of the recording tape T. The leader member 110 is pulled-out by a pull-out member (not illustrated) of a drive device. The pull-out member is usually provided at both side portions of a loading opening into which the recording tape cartridge 100 is loaded. Therefore, an opening 112 formed at the recording tape cartridge 100 is usually formed at a corner portion 102C of the case 102. Even if the opening 112 is not provided at the corner portion 102C, there are cases in which regions which are important to the functioning of the recording tape cartridge 100, such as a supporting shaft 116 of a door 114 which opens and closes the opening 112, or the like, exist in a vicinity of the corner portion 102C.
This corner portion 102C is the place where it is easiest to receive a concentration of stress when an impact is received such as when the recording tape cartridge 100 is dropped or the like. When a concentration of stress is received at the corner portion 102C, local, permanent deformation (crushing, bending, portions breaking off, or the like) occurs at that corner portion 102C, and problems arise in that the recording tape cartridge 100 cannot be loaded into a drive device, the recording tape T cannot be pulled out, the door 114 which opens and closes the opening 112 cannot open and close, or the like.
Further, even if permanent deformation does not occur, the leader member 110 (such as a leader tape or the like) may come out from its held position within the case 102, or get sandwiched between the peripheral wall 104A of the upper case 104 and the peripheral wall 106A of the lower case 106, or fly out of the case 102 if the door 114 opens, due to the occurrence of temporary flexural deformation, i.e., elastic deformation such that the peripheral wall 104A of the upper case 104 and the peripheral wall 106A of the lower case 106 move apart from one another.
Moreover, in order to prevent temporary flexural deformation, it has been thought to weld together or screw together the peripheral wall 104A of the upper case 104 and the peripheral wall 106A of the lower case 106 in a vicinity of the corner portion 102C. However, in such cases, conversely, the path by which the impact force (the energy) received at the time of a drop escapes is eliminated, and permanent deformation is promoted.